Sustained Ventricular Tachycardia as the First Presentation of Hereditary Transthyretin Amyloidosis With the Glu109Gln Mutation

Figures

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  Figure 1. Electrocardiogram at Presentation, After Cardioversion, and During Electrophysiological Study (A) Electrocardiogram (25 mm/s) at presentation showing monomorphic ventricular tachycardia at 240 beats/min. (B) Electrocardiogram (25 mm/s) after cardioversion showing sinus rhythm at around 80 beats/min with a diffuse pseudo-infarct pattern. (C) Electrocardiogram (50 mm/s) during electrophysiological study showing induced monomorphic ventricular tachycardia. The final QRS complexes reflect burst pacing used for termination of the arrhythmia.

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  Figure 2. Echocardiography at Presentation (A) Parasternal long axis image showing severe left ventricular hypertrophy. (B) Bulls-eye plot showing reduced left ventricular global longitudinal strain with a “cherry-on-top” pattern consistent with apical sparing. ANT = anterior; EDV = end-diastolic volume; GS = global strain; INF = inferior; IVSd = interventricular septum thickness, end-diastolic; LAT = lateral; LVIDd = left ventricular internal dimension, end-diastolic; LVPWd = left ventricular posterior wall thickness, end-diastolic; POST = posterior; SEPT = septal.

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  Figure 3. Cardiac Magnetic Resonance Imaging (A) 4-chamber view showing biatrial enlargement and severe biventricular hypertrophy. (B) Phase-sensitive inversion recovery image showing diffuse subendocardial and septal midmyocardial late gadolinium enhancement. (C) Native T1 mapping showing severely elevated T1 values in all the myocardium (1,141 milliseconds). (D) Extracellular volume mapping showing a calculated extracellular volume of 65%.

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  Figure 4. Technetium-99m–Labeled Bone Scintigraphy Technetium-99m–labeled bone scintigraphy showing Perugini grade 3 myocardial uptake.

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  Figure 5. Endomyocardial Biopsy With Congo Red Staining (A) Light microscopy demonstrating extracellular amyloid deposition (salmon-pink areas). (B) Apple-green birefringence of amyloid under polarized light.

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  Visual Summary. Sustained VT Revealing ATTR-CM (Glu109Gln) ATTR-CM = transthyretin amyloid cardiomyopathy; CMRI = cardiac magnetic resonance imaging; ECV = extracellular volume; EP = electrophysiology; GLS = global longitudinal strain; ICD = implantable cardioverter defibrillator; IVS = interventricular septum; LGE = late gadolinium enhancement; NT-proBNP = N-terminal pro-B-type natriuretic peptide; TnT = troponin T; TTR = transthyretin; VT = ventricular tachycardia.